Apkil 3, 1896.] 



SCIENCE. 



,521 



They stretch out to the west almost nnhrokenly to 

 the east fork of Black River; while numerous scat- 

 tered hills continue even beyond the middle fork of 

 the same stream. Toward the northwest similar 

 rooks occur at short intervals as far as Little Pilot 

 Knob, in Washington county. 



(Five lines referring the reader to maps.) 

 The central and most extensive portion of the crys- 

 talline is, as just stated, in the vicinity of Pilot Knob 

 and Iron Mountain, and occupies the median parts of 

 townships 33 and 34, north, in ranges III., IV. and V., 

 east of the fifth principal meridian, with occasional 

 extensions much farther in several directions. Tlie 

 crystalline area is almost unbroken for a distance 

 of 30 miles southeast and southwest of Bismarck) 

 which is situated near the northern margin of the 

 great central district. The other masses of similar 

 rook are much smaller and are widely scattered. 



(If a knowledge of such boundaries was possessed 

 by anyone other than myself and those who read my 

 manuscript, what a mistake for the State to pay out 

 so many hundred dollars and for me to spend so many 

 months' time in ascertaining them. ) 



PHYSIOGRAPHY. 



Topography. 



(A little less than two pages is of a general char- 

 acter which is relatively distinct from the manu- 

 script). 



Page 87. 



The various types of rooks give such characteristic 

 phases of topography to the different parts of the dis- 

 trict, that the true lithological nature of the rock 

 composing a hill may be readily inferred at a distance 

 of several miles. 



East of the great central mass of crystallines the 

 country is comparatively level, or rather not so rugged 

 as in the immediate vicinity of the porphyry hills. 

 In passing still farther toward the border of the area, 

 the topography continually changes ; the porphyry is 

 less frequently found in the valleys, and more and 

 more of the hills is composed of limestone. The 

 granites in various places form high, steep promi- 

 nences. To the west the difference in the surface re- 

 lief of the granite areas is even more marked. No 

 less than four of the most conspicuous elevations 

 here are made up of granite. One of these on the 

 East Fork of Black river, in the vicinity of the ' falls ' 

 (plate iii.), connects with the long rojv of porphyry 



(A little farther along five lines refer the reader to 

 maps. ) 



First: The central and most solid portions of the 

 Archsean is in townships 33 and 34 N, and in ranges 

 III., IV. and V. E, with occasional projections in dif- 

 fei'ent directions reaching much farther. 



(About a page and a half of manuscript follows 

 here giving more details of boundaries. ) 



Page 4. 



i. Topography. 



( About one page of manuscript is passed here con- 

 taining many facts mentioned in the printed part. ) 



Page 4. 



A little farther to the east, in the big granite area, 

 the country is comparatively level, or at least much 

 less rugged than in the immediate vicinity of the por- 

 phyry hills. This is so noticeable that one may well 

 speak of the characteristic topography of the granite 

 areas. The few high hills that occur almost invari- 

 ably grade into porphyry toward their summits. But 

 as we pass towards the border of our area, in any di- 

 rection, we find the topography changing. The por- 

 phyry is less frequently found in the valleys ; an 

 ever increasing proportion of the hills are composed 

 of Cambrian rooks ; and, strangest of all, the granites 

 in diSerent places become the constituents of high 

 and steep hills. 



( * * * Six lines of manuscript. ) 



To the west the difference in the topography of the 

 granite is often more marked. No less than four 

 prominent hills here are composed of granite, while 

 the valleys are never covered with it. One of these 

 is on the east bank of East Fork of Black river, in the 

 vicinity of the beautiful and picturesque 'falls' -' * *. 

 ( Here description is given in detail. ) 



The granite bill connects with a long row of promi- 

 nent porphyry hills, but it is higher than any of 

 them. The next most prominent one of the four lies 

 to the north about three miles in the angle between 

 the East Fork and the Imboden Fork. It is locally 

 called ' High Top, ' and well it deserves the name, for 

 it stands out prominent above all the hills near it. 

 According to the barometric measiu-ements made by 

 Mr. Kirk it rises 635 feet above the valley at its base, 

 which shows that it compares favorably with Shep- 

 herd Mountain, the biggest and highest porphyry hill 



